Of the four million cases of trauma cases each year that will require hospitalization, 200,000 will be classified as severe trauma. During the hospital stay, malnutrition is a major complication in about 50% of the patient population. The result is muscle wasting which is a major risk factor for increased morbidity and mortality. In the study proposal presented we postulate that supplementation with Beta-hydroxy-Beta-methylbutyrate (HMB), arginine and glutamine (HMB/Arg/Gln) to these severely traumatized patients can stem the loss of muscle tissue and whole body nitrogen and in turn decrease morbidity and mortality. This hypothesis is based on two recent studies showing the same nutritional mixture of HMB/Arg/Gln can reverse the muscle wasting associated with AIDS and Cancer. The hypermetabolic state seen in AIDS and cancer have a similar multilifactorial etiology seen in trauma. There is an increase in the mobilization of fat and muscle, increased or normal metabolic rate, increased protein breakdown, and an increased or normal glucose turnover. In addition, HMB alone has been shown to reduce nitrogen loss, decrease muscle proteolysis and muscle damage within the first 48 hours to three week after initiating supplementation. Male and female patients (n=100) will be recruited at the time of admittance to the Trauma ICU with an ISS of greater than 18 Patients who meet the inclusion/exclusion will be randomized to receive either 1) standard tube feed plus HMB/Arg/Gln, standard tube feed plus HMB alone, or standard tube feed (control) in a blinded fashion. Clinical outcomes measures will be assessed through out the hospital stay and on a outpatient basis on week 4 and week 12. Muscle proteolysis and nitrogen economy will be evaluated on daily basis while in the hospital and after 4 weeks on an out patient basis. If as expected, Phase I results confirm the effectiveness of the nutrient mixture in trauma patients. Expanded multicenter studies will be proposed in Phase II.